RE: ESC caught on fire?
Yes, the prop you are using is probably on the bleeding edge for that motor. I am wondering now if you blew/shorted the motor first which in turn overloaded the esc and burned it.
If you have another esc (30 amp or so) I would test the motor first (no prop) with a 3 cell lipo and make sure it's OK.
If the motor seems OK then the esc could have had some bad solder joints or a heat sink shorting out a transistor and the high amps and heat just brought everything together and did it in. Try another brand of esc and get or borrow a watt meter .